Re: Ada Successor Language

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On 2018-06-26 22:03, Dan'l Miller wrote:
> On Tuesday, June 26, 2018 at 2:29:48 PM UTC-5, Dmitry A. Kazakov wrote:
>> On 2018-06-26 20:47, Dan'l Miller wrote:
>>> On Tuesday, June 26, 2018 at 12:25:27 PM UTC-5, Dmitry A. Kazakov wrote:
>>>> On 2018-06-26 18:50, Dan'l Miller wrote:
>>>>> On Tuesday, June 26, 2018 at 10:38:50 AM UTC-5, Simon Wright wrote:
>>>>>> ric.wai88@gmail.com writes:
>>>>>>
>>>>>>> I hope I can opt to be out-side of this "Ada" community who seem bent
>>>>>>> on wasting copious time determining overly contrived ways of
>>>>>>> destroying Ada from the inside out.. Apparently because Ada's
>>>>>>> carefully enforced discipline is too inconvenient, or something.
>>>>>>
>>>>>> I agree with you. It feels as though we have a few people around who
>>>>>> enjoy wild flights of fancy.
>>>>>
>>>>> I agree.  Ada does not need records with external-to-record tags.
>>>>
>>>> Ada already has them, since 1983.
>>>
>>> Wait.  Ada83 already has what you are proposing regarding 'Class for untagged records, eh?
>>
>> Ada 83 has "untagged" records, yes.
> 
> But Ada83 does not have your 'Class for untagged types.

Your question was about naming "untagged" records and that they may 
break something if introduced. Records are defined in RM 3.8. They 
cannot be introduced because they are already there. They cannot break 
anything for the same reason. So far clear?

Adding a class-wide type cannot break anything for the reason of being a 
distinct type. Whatever semantic T'Class has it is related to the 
objects of this and only this type, because Ada has strong nominal type 
system. OK?

>>> But merely 3 hours ago you said that your proposing of something that is already there would be pointless:
>>
>> Exactly. I never proposed "untagged" records. I proposed a method to
>> have a class-wide type rooted in a non-tagged type, not only records but
>> scalar types, array types, even tasks and protected objects as well.
> 
> Ahhh, now your words have finally circled back to that bad idea that threatens to bring C++ slicing to Ada when the compiler's choice of strong type differed from the programmer's intended strong type.  Welcome back!  Many happy returns.

I have no idea about C++ slicing anything. Even less about Ada choosing 
types. Ada is a strongly manifestedly typed language. There is no way 
the compiler could choose a type for the programmer. There is no type 
inference in Ada and there is no such thing in my proposal. Please 
explain what exactly you mean.

>>>>> (What the heck would we call these, btw?  Untagged tagged records?  Tagged untagged records?)
>>>>
>>>> There is no special name in RM 3.8, just "record".
>>>
>>> Ummmm.  _LRM_'s §3.8 says nothing about your 'Class usage on untagged records.
>>
>> It says about records, all records including "untagged" ones.
> 
> But not your 'Class for untagged records using your external-to-record tag.

Yes, and?

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de